1. Field of the Invention
The present invention relates to a metal mold unit for use in injection molding of synthetic resin.
2. Related Art
FIG. 3 shows a conventional metal mold unit for injectionmolding synthetic resin as comprising, in combination, a metal mold 1 consisting of a cavity 1a and a core 1b, a stationary metal mold supporting member 2 and a movable metal mold supporting member 3. These cavity 1a and core 1b are releasably fixed to the stationary and movable metal mold supporting member 2 and 3, respectively. The whole assembly is attached to an injection molding machine (not shown), and then the opposing metal mold sections 1a and 1b are made to open and close, thereby permitting injection molding of resin material and removal of rein products.
As shown, each metal mold section 1 has a fluid channel 5.
A heating fluid is made to flow in the fluid channel to control the mold temperature in use.
The conventional metal mold unit is so complicated in structure, particularly in attachment of metal sections to the stationary and movable supporting members that replacement of a new metal mold for shaping a different resin article would involve much man-hour, accordingly causing poor operating efficiency.
In an attempt to avoid this problem, a metal mold is integrally connected to a holder as a whole unit, and when a metal mold is changed in an injection molding machine, a metal mold unit having a desired metal mold intergrally connected to a holder is put in place. In this connection disadvantageously a metal mold holder, which, otherwise, could be repeatedly used for different metal molds, must be made for each and every metal mold. This involves much expense in making metal mold units.